苯甲酰基硫代苯甲酸-S-苯酯的激发态性质

通过激光闪光光解技术对苯甲酰基硫代苯甲酸-S-苯酯激发态的瞬态吸收光谱和胺对该化合物激发态的猝灭过程进行了研究,结合稳态光化学研究的结果,发现该化合物在强光激发下,其激发三重态量增加,由于其弱的C-S键,在强光照射下很快发生分子断裂。在与胺组成的体系中,其猝灭过程较特殊,主要生成自由基离子,但也可能通过质子转移生成半片呐醇自由基和胺自由基。研究发现,该过程与胺的离子化电位(I_p)有关,低I_p值有利于自由基离子的生成,此外也与受体分子的性质有关,BPTB分子具有较强接受电子的能力也促进了自由基离子的生成。

EXCITED STATE OF p-BENZOYL s-PHENYL THIOBENZOATE

The time resolved transient spectra of the excited state of p-benzoyl s-phenyl thiobenzoate (BPTB)and its quenching processes were studied in this work by laser flash photolysis method. For the amine containing systems, the quenching process was different from that described above. The ion radicals became the main products, and the pinacol radical formed from the proton transfer was reduced. The results show that this process depends strongly on the ionic potential(I_p) of amines. The amine with low I_p value favors the formation of the ionic radicals. In addition, it also depends on the property of the acceptor used. It was evidently found in experiment that BPTB is a stronger electron acceptor than BP which promotes the formation of ionic radicals.